As oil spills into the Gulf of Mexico from the damaged Deepwater Horizon oil rig near Louisiana, UC Davis wildlife experts are advising officials on the scene by telephone and standing by to travel to the disaster site if needed.

The UC Davis Wildlife Health Center at the School of Veterinary Medicine manages California’s Oiled Wildlife Care Network, widely considered the world's expert in capturing and caring for oiled birds and marine mammals, such as sea otters, seals and sea lions. The center also has expertise on oil's impacts on whales, dolphins and porpoises, and wrote the National Response Guidelines for the National Oceanic and Atmospheric Administration's National Marine Fisheries Service.

Veterinarian Michael Ziccardi, an associate professor of clinical wildlife health at the UC Davis Wildlife Health Center and director of the Oiled Wildlife Care Network, said that as long as the spill stays off the Gulf shoreline, the animals most at risk from the crude oil are sea turtles. Whales and smaller cetaceans are also at risk it they swim through the area.

If the oil reaches the shoreline, it could have serious impact on marine seabirds, such as brown pelicans. The Mississippi Flyway is a critical thoroughfare for migratory birds, and is now experiencing its peak migratory period, Ziccardi said.

Oil's potential effects on the marine mammals found in the Gulf of Mexico include:

• Skin: Adult dolphins and whales are protected from cold water by a thick blubber layer, but young animals often have not yet developed this layer. Oil that directly contacts the skin and mucous membranes can cause painful chemical burns that may become infected.

• Internal organs: Swallowing oil, or eating oiled prey, can injure a dolphin or whale's gastrointestinal tract, which can cause direct damage or impair the ability to digest and absorb food. Metabolism of absorbed oil components by the kidney and liver can damage those organs as well. Oil fumes can irritate or injure the respiratory tract, leading to inflammation and pneumonia.

• Reproduction: Data are limited; among orcas (killer whales) after the 1989 Exxon Valdez oil tanker disaster, the worst oil spill in United States history, two pods lost approximately 40 percent of their numbers. Since that time, the reproductive capacity of these pods has been reduced by the loss of females, and only about half of newborn calves are surviving.

Oil's potential effects on birds include:

• Skin and feathers: Oil removes the insulative properties of feathers, allowing cold water to seep in next to the skin and causing a decrease in the oiled bird's body temperature. To combat this decrease, the bird's metabolism increases, causing a greater need for food. At the same time, oiled birds do not float well; their swimming and foraging ability decreases; and they often cannot fly and will haul out of the water. Lighter, more volatile petroleum products (such as kerosene and jet fuel) can also cause significant skin burns and eye irritation.

• Internal organs: Because birds preen themselves meticulously with their bills to maintain their insulating air layer, an oiled bird usually ends up swallowing some oil. This can cause direct damage to the gastrointestinal tract, leading to ulcers, diarrhea and a decreased ability to absorb nutrients. If the volatile components of the oil are inhaled, it can result in pneumonia, neurological damage, or absorption of chemicals that can lead to cancer. Metabolism of the oil components by the kidney and liver can damage those organs as well. Lastly, oil (and the stress of being oiled) can damage or destroy the blood cells that carry oxygen or fight infections.

• Reproduction: Oil can have drastic effects on each stage of bird reproduction. Studies on the effects of a single drop of oil on eggs from different species of birds have shown significant mortality and developmental defects in embryos. Other research has shown that oiled adult birds more frequently abandon hatchlings or reduce their breeding activities.
UC Davis: A global model

The Oiled Wildlife Care Network was established after the Exxon Valdez disaster. An estimated 250,000 seabirds, 2,800 sea otters, 300 harbor seals, 250 bald eagles and as many as 22 killer whales were killed in the disaster.

The network has become the world's most sophisticated spill-rescue program and a model for other countries. It has 12 facilities that can immediately care for birds, mammals or sea turtles that are impacted by oil spills in California’s waters, with 29 organizations at the ready.

In contrast, after the Exxon Valdez spill, it took rescuers weeks to establish emergency veterinary hospitals; in the end, only 801 birds and 197 otters were rehabilitated and released.

When oiled animals arrive at one of the network's emergency rooms, they're also arriving at a university research center. The Oiled Wildlife Care Network collects detailed physical information about every animal it receives, contributing to a huge database of scientific information that can help improve both the short-term care and the long-term health of oiled animals and their populations. Also, the network provides up to $250,000 in grants annually to researchers in California and elsewhere studying the effects of oil on wildlife. It has distributed more than $2 million in grants to more than 100 research projects since 1996.

"Ours is only program in the world that puts this level of research funding toward oiled wildlife care," said Ziccardi.

About UC Davis

For more than 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 32,000 students, an annual research budget that exceeds $600 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges — Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science. It also houses six professional schools — Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.
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